The present invention relates to the manufacture of a screen frame for use in screen printing, and more particularly to a method of filler taping and a method of filling in which the attachment of a tape and application of a filler liquid onto the four sides of a screen frame are performed after stretching of the screen.
At the time of screen printing, an area where no emulsion of the type used for producing a screen plate is applied must be formed at the marginal edge portions of the screen before application of the emulsion. If an area space with a width of 10 to 20 mm is to be provided for a 950 mm square frame, it is difficult to form this area accurately, and it thus becomes difficult to perform subsequent processing. More importantly, there is a need to prevent softening of the adhesive that is used to hold the screen in a stretched condition during development of the emulsion as such softening would make it impossible to obtain accurate screening. For these reasons, it is necessary to provide taping and filling at the four sides of the frame in the vicinity of the edges thereof.
Heretofore, taping and application of a filling liquid on the rear side of a screen have been carried out manually. However, there are many cases where a tape is adhered unevenly, and it generally takes about 20 minutes to perform these operations for one frame.
In recent years, printed circuit boards on which various electronic parts are mounted have come to be required in large quantities and such involves mass production systems in which screen printing is employed. Hence, the demand for screen plate frames has also increased, and industry has been called upon to supply them at low cost. The conventional manual operations cannot meet these requirements in terms of production quantity and cost.